A cable modem (CM) is a type of network device or modem that provides data communication by radio frequency channels on a hybrid fibre coax (HFC) and/or radio frequency over glass (RFoG) infrastructure.
Cable modems utilize the HFC and RFoG networks to deliver high bandwidth broadband internet access. The cable modems provide relatively low cost internet access at relatively high speeds.
A number of cable modems typically share the HFC and/or RFoG infrastructure with a limited number of channels and frequencies. Interference can occur when multiple cable modems attempt to utilize the same channel(s). This interference can degrade or disrupt the broadband internet access. The interference can include upstream to downstream interference.